package com.interceptor;

import com.po.User;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

public class LoginInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request,
                             HttpServletResponse response,Object handler) throws Exception{
        //获取请求的URL
        String url = request.getRequestURI();
        //URL：除了Index.jsp是可以公开访问的，其他的URL都进行拦截
        if(url.indexOf("/login")>0){
            return true;
        }
        //获取session
        HttpSession session = request.getSession();
        User user = (User) session.getAttribute("USER_SESSION");
        //判断Session中是否有用户数据,如果有,则返回true,继续向下执行
        if(user != null){
            return true;
        }
        //不符合条件的给出提示信息,并转发到登陆页面
        request.setAttribute("msg","您还没有登陆,请先登陆!");
        request.getRequestDispatcher("/index.jsp").forward(request,response);
        return false;
    }
    @Override
    public void postHandle(HttpServletRequest request,
                           HttpServletResponse response, Object handler,
                           ModelAndView modelAndView)throws Exception{
    }
    @Override
    public void afterCompletion(HttpServletRequest request,
                                HttpServletResponse response,Object handler,Exception ex)throws Exception{
    }
}
